Sugar apple fruit are widely appreciated because of their flavor and functional qualities. However, the final value of the fruit varies according to its physical, physicochemical, and organoleptic qualities. The production and attributes that make up the quality of fruit can be influenced by climatic seasonality in both seasons (dry and wet). Therefore, this work aimed to evaluate whether the production and quality of fruit production of different size classes of A. squamosa L. in two seasons are affected by climatic seasonality. The experiment consisted of a randomized block design, with 4 blocks and 10 plants per block. The variables evaluated were number of fruit per hectare, production, and yield. The postharvest evaluation of the fruit consisted of a completely randomized experimental design, in a 3 × 2 factorial scheme, which referred to the three sizes and two seasons, and evaluated fruit length and diameter; firmness; fruit, bark, and seed weight; number of seeds; soluble solids; hydrogen ionic potential (pH); titratable acidity (TA); and ratio. The 2014 season had larger fruit in relation to those of the 2015 season; conversely, it showed a lower number of fruit per plant, production, and yield, besides inferior organoleptic quality. Fruit of size class 2 stood out in the 2014 season because of their physical characteristics. However, they had inferior organoleptic quality when compared with fruit of the same size collected during the 2015 season. Fruit of size class 3 (≥8.1 cm) had greater firmness, providing longer durability and shelf life.

Sugar apples have attracted attention in recent years due to their medicinal and nutritional properties. However, the shelf life of sugar apples is one of the most concerning problems owing to their perishability. This work aimed to determine the ideal harvest time for sugar apple fruits in relation to different classes of carpel interspaces. Therefore, fruits were classified into three stages according to the carpel interspace: stage 1 (0.0 - 2.0 mm); stage 2 (2.1 - 3.0 mm); and stage 3 (3.0 - 4.0 mm). After harvesting, the fruits were evaluated daily in the laboratory regarding their physical and physicochemical aspects until they reached the point of consumption (horticultural maturation). The following variables were evaluated: fruit diameter and length (mm); fruit, peel, pulp, and seed masses (g); color index, including the chromatic attributes L* (luminosity), C* (chroma), and h* (hue angle); bark firmness (N); soluble solids (°Brix); titratable acidity (g citric acid 100 g-1 of pulp-1); pulp yield; and ratio SS/TA. Fruits at stage 3 showed larger diameters, less firmness, and better chromaticity means. Fruits at stages 2 and 3 had eight days of postharvest life. However, fruits at stage 2 took longer for 50% of the fruits to be ready for consumption. The results demonstrate that stages 2 and 3 can be determinants for the harvest time of sugar apples.

The success in the application of artificial pollination techniques, aspects of floral biology should receive special attention, especially regarding the viability studies of pollen grains. In this sense, two experiments were carried out, aiming to determine the floral stages: floral opening (anthesis), female, male and senescence stages of A. squamosa L flowers under tropical climate conditions, and to evaluate the germination and viability of pollen grains submitted to different storage conditions. In the first experiment, observations and data collection began when flowers were still closed. Readings were taken every two hours for 46 hours until all the flowers reached the senescence stage. For the second, the experimental design was completely randomized, in a 2 x 7 factorial scheme, with 2 storage conditions (environment at 27 ± 2°C and refrigerated at 5 ± 2°C) and 7 pollen grain conditioning times (0, 4, 8, 12, 16, 20 and 24 hours), with 4 repetitions for the analysis of pollen grain germination and 3 repetitions for the analysis of pollen grain viability, and each repetition consisted of one blade. The variables evaluated were percentage of viable and non-viable pollen grains and percentage of germinated and non-germinated pollen grains. For tropical climatic conditions, the flower anthesis (female stage) of the sugar-apple begins at 00:00 h, extending until 12:00h on the same day. The flowers of the tree reach a functionally staminate stage (male stage) from 6 a.m. the next day. Pollen grains stored at room conditions (27 ± 2°C) remain viable for up to 24 hours after collection, showing that storage in a cold environment at low temperatures (5 ± 2°C) is not necessary. Seed pollen grains have a germination percentage of 51.25% when stored under ambient conditions (27 ± 2°C) for up to 4 hours after collection.

Sugar apple (Annona squamosa L.) is a commercially significant fruit species due to its nutritional qualities. The state of Roraima has excellent soil and climatic conditions for the cultivation of the species. However, no studies on the phenological behavior of this plant have been reported in the literature. In this context, the objective of this work was to investigate the vegetative and reproductive phenological behavior of sugar apple under the savanna conditions of the state of Roraima. The experiment was carried out in four seasons of the year (2014/2014 and 2015/2015 rainy season and 2014/2015 and 2015/2016 Summer). Production pruning was carried out in February 2014 (2014.1 cycle), September 2014 (2014.2 cycle), February 2015 (2015.1 cycle) and September 2015 (2015.2 cycle). Forty plants were monitored during the experiment and evaluated every three days for the following variables: beginning date of bud swelling; duration of flowering; and fruit harvest time. From the observed data, the periods (days) between each phenological stage were calculated: pruning/bud swelling; pruning/beginning of flowering; bud swelling/anthesis; pruning/anthesis; anthesis/beginning of fruit harvest; duration of fruit harvest, and crop cycle (production pruning/harvest). The duration of the cycle, from the production pruning to the harvest varied according to the productive period, recording 146 days for the 2014.1 cycle and 127 days for the 2014.2 cycle, which proves that the phenological behavior of the species is influenced by climatic conditions.

Camu-camu fruits have high functional importance and great potential as food. Knowing and determining the nutrients present in its fruitsis crucial, in order to understand the relationship between consumption and human health. For this reason, the objective of this work was to evaluate qualitative attributes, such as organic acids content, antioxidant capacity and functional potential of different parts of camu-camu fruit. The fruit used in the present study were collected in the state of Amazonas, Brazil, and analyzed at the University of Florida, Gainesville, U.S.A. Seed, peel, pulp, pulp+peel, and whole fruit were evaluated regarding pH, soluble solids, titratable acidity, and levels of ascorbic acid, phenolic compounds, anthocyanins, and flavonoids. Antioxidant activity was evaluated by the Ferric Reducing Antioxidant Power (FRAP) and Diphenyl-1-picrylhydrazyl (DPPH) methods. Based on the results, camucamu fruit proved to be a good source of acids, and the pulp is the part that is most concentrated in organic acids. Also, the pulp presents the highest amount of phenolic compounds and highest antioxidant activity. The peel had relatively higher amount of pigments, anthocyanins and flavonoids, and higher concentration of ascorbic acid, proving that it can also be used as a source of bioactive compounds.